From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2541EC43441 for ; Wed, 21 Nov 2018 21:22:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E198E204FD for ; Wed, 21 Nov 2018 21:22:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E198E204FD Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389842AbeKVH6M (ORCPT ); Thu, 22 Nov 2018 02:58:12 -0500 Received: from mail.bootlin.com ([62.4.15.54]:34780 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726791AbeKVH6M (ORCPT ); Thu, 22 Nov 2018 02:58:12 -0500 Received: by mail.bootlin.com (Postfix, from userid 110) id 6170420D73; Wed, 21 Nov 2018 22:22:07 +0100 (CET) Received: from localhost (unknown [88.191.26.124]) by mail.bootlin.com (Postfix) with ESMTPSA id 387E720510; Wed, 21 Nov 2018 22:21:57 +0100 (CET) Date: Wed, 21 Nov 2018 22:21:57 +0100 From: Alexandre Belloni To: Rob Herring Cc: radu_nicolae.pirea@upb.ro, Richard Genoud , Lee Jones , Mark Rutland , Nicolas Ferre , Ludovic Desroches , Mark Brown , devicetree@vger.kernel.org, "linux-kernel@vger.kernel.org" , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" , linux-spi Subject: Re: [PATCH 2/3] dt-bindings: mfd: atmel-usart: add DMA bindings for SPI mode Message-ID: <20181121212157.GD12656@piout.net> References: <20181121112732.15690-1-radu_nicolae.pirea@upb.ro> <20181121112732.15690-3-radu_nicolae.pirea@upb.ro> <20181121164820.GC12656@piout.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21/11/2018 14:52:29-0600, Rob Herring wrote: > On Wed, Nov 21, 2018 at 10:48 AM Alexandre Belloni > wrote: > > > > Hi Rob, > > > > On 21/11/2018 10:41:01-0600, Rob Herring wrote: > > > > +Optional properties in serial and SPI mode: > > > > +- dma bindings for dma transfer: > > > > + - dmas: DMA specifier, consisting of a phandle to DMA controller node, > > > > + memory peripheral interface and USART DMA channel ID, FIFO configuration. > > > > + Refer to dma.txt and atmel-dma.txt for details. > > > > + - dma-names: "rx" for RX channel, "tx" for TX channel. > > > > > > > + dma-names = "tx", "rx"; > > > > > > The dma-names should have a defined order. > > > > > > > Why is that? Isn't the purpose of names to get rid of any particular > > ordering? > > Because a fundamental rule of DT is the order is defined and > important. The purpose was to allow for cases that had a variable > number of entries, but even a variable number still have a defined > order. > Thank you for the clarification! -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com